RETINAL PROSTHESIS WITH EFFICIENT PROCESSING CIRCUITS

• US 20140031931A1
• Filed: 09/05/2013
• Published: 01/30/2014
• Est. Priority Date: 02/24/2011
• Status: Active Grant

• Current Assignee: Nano-Retina Inc.
• Original Assignee: Nano-Retina Inc.
• Inventors: Liran, Tuvia, Gefen, Ra'anan
• Granted Patent: US 9,192,464 B2
• Time in Patent Office: Days
• US Class Current: 623/6.63
• CPC Class Codes: A61F 2/14 Eye parts, e.g. lenses, corneal implants; Implanting instruments specially adapted therefor; Artificial eyes
• CPC Class Codes: A61N 1/36046 of the eye

Abstract

A medical device includes an array of electrodes, configured for implantation in contact with tissue in an eye of a living subject. Driver circuitry is configured to drive the electrodes in an alternating pattern, such that different groups of the electrodes are driven to stimulate the tissue during different, predetermined respective time periods. A power sensor, may be coupled to deactivate a first group of the electrodes when the available electrical power drops below a predetermined threshold, while a second group of the electrodes remains active. Other embodiments are also described.

Claims

1. A medical device, comprising:

an array of electrodes, configured for implantation in contact with tissue in an eye of a living subject; and

driver circuitry, configured to drive the electrodes in an alternating pattern, such that different groups of the electrodes are driven to stimulate the tissue during different, predetermined respective time periods.

2. The device according to claim 1, wherein the driver circuitry is configured to hold the electrodes at a common potential in time intervals outside the respective time periods so that the electrodes serve as return electrodes during the time intervals.

3. The device according to claim 2, wherein the driver circuitry comprises memory elements for returning the electrodes to a common level following the respective time periods.

4. The device according to claim 1, wherein some of the different time periods overlap, and wherein the groups are selected so that the time periods during which mutually-adjacent electrodes are driven do not overlap.

5. The device according to claim 1, wherein the driver circuitry is coupled to drive the electrodes with pulses having frequencies determined responsively to an intensity of light that is incident on the device.

6. The device according to claim 5, wherein the device comprises light-sensing elements, coupled to sense the intensity of the light and to provide respective signals to the driver circuitry, and wherein the frequencies are determined responsively to differences between the respective signals and a mean level of the signals.

7. The device according to claim 6, wherein the driver circuitry is configured to generate an overshoot in the frequencies in response to a change in the intensity.

8. The device according to claim 1, and comprising a power source coupled to supply electrical power to the driver circuitry, and a power sensor, which is configured to monitor a voltage output by the power supply and to deactivate a first group of the electrodes when the voltage drops below a predetermined threshold, while a second group of the electrodes remains active.

63. The device according to claim 3, wherein the memory elements comprise a flip-flop.

9-33. -33. (canceled)

34. A method for neural stimulation, comprising:

providing an array of electrodes for implantation in contact with tissue in an eye of a living subject; and

driving the electrodes in an alternating pattern, such that different groups of the electrodes are driven to stimulate the tissue during different, predetermined respective time periods.

35. The method according to claim 34, wherein driving the electrodes comprises holding the electrodes at a common potential in time intervals outside the respective time periods so that the electrodes serve as return electrodes during the time intervals.

36. The method according to claim 35, wherein holding the electrodes comprises coupling a memory element to return the electrodes to a common level following the respective time periods.

37. The method according to claim 34, wherein some of the different time periods overlap, and wherein the groups are selected so that the time periods during which mutually-adjacent electrodes are driven do not overlap.

38. The method according to claim 34, wherein the method comprises providing light-sensing elements for implantation in the eye to sense an intensity of light and to output respective signals responsively to the intensity, and wherein the driving the electrodes comprises applying pulses to the electrodes at frequencies determined responsively to the signals.

39. The method according to claim 38, wherein the frequencies are determined responsively to differences between the respective signals and a mean level of the signals.

40. The method according to claim 39, wherein applying the pulses comprises generating an overshoot in the frequencies in response to a change in the intensity of the light that is incident on the light-sensing elements.

41. The method according to claim 34, wherein driving the electrodes comprises deactivating a first group of the electrodes when a level of electrical power supplied for driving the electrodes drops below a predetermined threshold, while continuing to provide the pulses to a second group of the electrodes.

64. The method according to claim 36, wherein the memory element comprises a flip-flop.

42-62. -62. (canceled)